The invention relates to an integrated circuit (chip).
Chips are usually securely soldered on printed circuit boards or attached on a carrier in some other way. For various reasons, however, it is desired to mount the chip on the carrier reversibly, i.e. such that it can be detached without being destroyed. Such technology is of advantage, for example, for carrying out chip tests and also makes it much easier to exchange defective chips.
Checking the functionality of chips generally takes place by means of special testers. In a conventional chip test for packaged chips, such as for example TSOP chips (TSOP: Thin Small Outline Package) or BGA chips (BGA: Ball Grid Array), the chips are inserted into test sockets which have complicated mechanical constructions and must perform mechanical compensating movements to connect the chip contacts, usually formed as soldered contacts, to the test board. The mechanical complexity of test sockets of this type is therefore relatively great and the type of connection is complicated. With increasing integration and pattern spacings becoming ever smaller, such mechanical contacting is becoming more and more difficult. This applies in particular to more recent generations of unpackaged chips, such as for example CSP chips (CSP: Chip Size Package)
The exchange of defective chips of multichip modules (MCM) has until now been performed by unsoldering the defective part, and cleaning and soldering in a good part. This known exchanging process is not only costly and time-consuming, it also cannot be automated very well.
In the case of packaged chips with legs (Lead Frame Based Packages), the exchange of the chips can also be performed with the aid of a socket which is soldered onto the carrier. However, the contacts of chips of a more recent generation are differently designed (as small balls), making this solution obsolete.
It is an object of the present invention to provide a technology for mounting chips on printed circuit boards or other carriers with which the chip can be attached on the carrier in such a way that it can be exchanged without being damaged.
According to the invention, for an integrated circuit chip, attachment elements are provided for attaching the chip on a carrier. The attachment elements of the chip are designed such that they can enter into a releasable connection with corresponding attachment elements formed on the carrier. The attachment elements are arranged on the unpackaged chip.